Request for MPPE patch to kernel

Forum: User Feedback
Topic: Request for MPPE patch to kernel
started by: WDef

Posted by WDef on Aug. 06 2008,21:18

Hi Robert

Wondering if it would be possible on your next rebuild of the 2.4.31 kernel to apply the MPPE/MPPC kernel module patch for this kernel from

< http://mppe-mppc.alphacron.de/ >

I can't see standalone sources for this module on that site.

This should allow VPN clients using PPTP (such as PPTPClient) to work on dsl: < http://pptpclient.sourceforge.net/#download >

Otherwise, short of compiling the kernel and remastering, I'll have to boot Puppy or Fedora or something to access a necessary VPN :=(

(On tinycore this shouldn't be needed since this module has already been merged with the mainline 2.6 kernel, though it might need to be enabled in the config).

Posted by curaga on Aug. 07 2008,10:32

Why wouldn't you just build the module and create an extension? It wouldn't require building the whole kernel.

Posted by roberts on Aug. 07 2008,16:18

I agree, a Microsoft only protocol, and one that I would not be able to test ( I do not own nor use any Microsoft product ) would be better off as a module. An extension for those who do need this capability would be a better approach.

Posted by WDef on Aug. 07 2008,16:56

Point taken.

It doesn't require testing with any MS product locally however - this protocol is used by VPNs using PPTP (seems to be most of them now) and this module is now part of the 2.6 kernel as I said.

Curaga: I think it may require a kernel rebuild since the patch and instructions seem to change more than one kernel configuration - if these are not different to dsl's default config and no other part of the tree get changed then I suppose it can be built standalone and inserted safely into the stock dsl kernel. But instructions rightly say to rebuild the kernel to avoid any possible mismatch. An exception is something like loopaes (in the specific case of dsl) where no alteration to dsl's .config is necessary since it already has the loop driver as a module.

A different-enough .config might be sufficient reason on its own not to include it in base dsl however.

Posted by WDef on Aug. 08 2008,23:11

I've patched and recompiled the kernel, and built the user space utils (ppp of an appropriate version and the current pptp-1.7.2.

The modules do insert into dsl's running kernel, but pptpsetup throws an error "can't locate module ppp-compress-18" and "couldn't find MPPE support in kernel".

So I think I may have been right - I'll have to swap out dsl's kernel for the patched kernel to get the mppe module working correctly.

EDIT: Maybe not. If I add this to /etc/modules.conf:

alias ppp-compress-18 ppp_mppe_mppc

this error goes away.